In a heated letter to James Comey released Sunday, Reid accused the FBI chief of holding back “explosive” information about Donald Trump’s close Russian ties and possibly violating the Hatch Act, which bars government officials from using their positions to influence an election.

“Your actions in recent months have demonstrated a disturbing double standard for the treatment of sensitive information, with what appears to be a clear intent to aid one political party over another,” Reid wrote, adding that through Comey’s “partisan actions, you may have broken the law.”

Ethan Miller/Getty

Ethan Miller/Getty

Reid, who is retiring at the end of his term, continued that Comey’s “highly selective approach to publicizing information, along with your timing, was intended for the success or failure of a partisan candidate or political group.”

“In my communications with you and other top officials in the national security community, it has become clear that you possess explosive information about the close ties and coordination between Donald Trump, his top advisors and the Russian government – a foreign interest openly hostile to the United States, which Trump praises at every opportunity,” Reid wrote.

“The public has a right to know this information.”

According to the New York Times, federal investigators have obtained the warrant needed to start reviewing the 650,000 emails found on a laptop used by top Clinton aide Huma Abedin and her husband, Anthony Weiner. The warrant came two days after Comey revealed the existence of the emails in a letter to the Senate Judiciary Committee.

“This letter, which was quickly posted on the internet, made highly unusual public statements about an F.B.I. investigation concerning a candidate in the election,” Painter wrote. “The letter was sent in violation of a longstanding Justice Department policy of not discussing specifics about pending investigations with others, including members of Congress. According to some news reports on Saturday, the letter was sent before the F.B.I. had even obtained the search warrant that it needed to look at the newly discovered emails. And it was sent days before the election, at a time when many Americans are already voting.”

The situation is further complicated because, as Comey said in his letter, the FBI does not yet know what the emails are or if they are linked to Clinton’s previous investigation.